Aim/Background: This study examines the meaning of patient autonomy in healthcare in the clinical context of individuals engaged with self-testing technology. Patient autonomy has gained increased prominence in healthcare ethics, policy and practice in recent decades. This poses challenges when autonomy competes with other moral principles. The proliferation of self-testing technology provides a contextualised example of this ideological shift. The philosophical assumption underpinning these technologies is that they facilitate greater autonomy through self-management. This study explores that assumption and the wider reverence to autonomy in healthcare. Methodology: Heideggerian phenomenology provides an overarching philosophy for the research. The study adopts an empirical ethics research design, which integrates philosophical analysis and empirical enquiry in a cyclical fashion. Ethical analysis precedes and follows empirical investigation. Interpretive phenomenology is utilised to elicit the lived experience of autonomy among 12 individuals with diabetes engaged in the self-testing process. The perspectives of prominent stakeholders such as healthcare professionals and scientific community members are also sought. Data is analysed collectively in accordance with a hermeneutic approach. Findings/Recommendations: The study illuminates the ethical principle of autonomy in a practical context. Findings reveal an understanding of Autonomy as lived: The interdependent phenomenon of autonomy in self-testing whereby the patient experience of autonomy is underpinned by three inter-reliant relationships - Relationship with device, Relationship with illness and Relationship with healthcare provider. Findings suggest that autonomy is a contextualised, relational process, which exists as a continuum and occurs within constraints. The concept of ‘negotiated autonomy’ is suggested as a means to operationalise Autonomy as lived within the patient/healthcare professional relationship. Findings have implications for bioethicists, policy-makers, healthcare professionals and patients when conceptualising and operationalising autonomy. The study also highlights the benefit of dialogue among the scientific community regarding the social and ethical dimensions of emerging technologies.